1. Field of the Invention
This invention relates to persistent and reliable delivery of event messages, including event messages in file server systems in which it is desired to maintain reliable file system consistency.
2. Related Art
In systems that provide services to clients, such as those including file servers and similar devices, it often occurs that the system, or some subsystem within that system, generates a message indicating the occurrence of a special event. Typically, the special event is an error of some kind, and the message conveys information regarding the nature of the special event, such as the type of error and the subsystem within which the error occurred. Many systems that provide services, including file servers, make efforts to assure that the services are reliably provided, and that the system providing the services is in a consistent state at all times. Thus, such systems find it advantageous to assure that all state information regarding the system, including state information relating to error messages, is persistently and reliably maintained. Such systems also find it advantageous to assure that all event messages are reliably delivered and persistently maintained until delivery is confirmed by the intended recipient of the event message.
Accordingly, it would be advantageous to provide a technique for persistent and reliable delivery of event messages, that is not subject to the drawbacks of the known art. Preferably, those parts of the system responsible for delivering event messages are able to persistently maintain those event messages until delivery of those event messages has been confirmed by the intended recipient of the event message. Moreover, those parts of the system responsible for recovering from system crashes and other system errors are able to persistently maintain those event messages until delivery, even after recovery from system crashes or other system errors.